President Obama might have won the Nobel Peace Prize for promoting nuclear disarmament and the Cold War is now history, but there are still around 70,000 atomic weapons on the planet today.

So what would happen if one fell on Birmingham?

Well wonder no more as a shocking new website, Carloslabs, allows you to NUKE your own city with your own choice of bomb and then see the terrfifying consequences.

It shows that if US bombers had got lost on their way to Hiroshima and dropped the first ever nuclear bomb – called Little Boy – on us instead, we would be facing a blast the equivalent of 12 kilotons of TNT.

Buildings would be flattened up to a mile from the epicentre, with the remains flying through the air like shrapnel, while a firestorm would travel double that distance.

The city centre would be devastated while the leafy suburbs of the likes of Edgbaston would avoid much of the destruction, although residents may start to show signs of radiation sickness in time.

But Little Boy was just small fry compared with the Tsar Bomb.

Tested in 1961 within the Arctic Circle, this Russian hydrogen explosive detonated with the force of 50 megatons – TEN TIMES the explosives used in World War II, including the nukes dropped on Japan.

The biggest bang let off by humanity so far would have caused third degree burns 62 miles away, while a shockwave travelled around the Earth three times and caused damage as far as 620 miles away in Sweden.

The resultant mushroom cloud was 40 miles high – seven times higher than Mount Everest – and 25 miles wide.

So if this biggest of the bad went off in Brum, it would be all over for the country’s second city. Everyone within around 35 miles of the explosion would instantly be given a radioactive tan that lasts.

And even if you live in Worcester you might have escaped the worst of the blast but the nuclear fallout would make life very uncomfortable, to say the least.

But whatever man can do, nature can do better.

Our little nukes wilt in the face of the explosion that wiped out the dinosaurs 65 million years ago. A meteor at least six miles wide, travelling at 15 miles per second, smashed off what is now the coast of Mexico with a force of 100 million megatons. That’s TWO MILLION times as powerful as the Tsar Bomb.

If the hell rock paid a visit to Birmingham it would obliterate everything within 300 miles. All the cities, towns, villages, people, trees gone – vaporised in a flash.

But what if you managed to survive? Well for the dino-killer it doesn’t really matter where you live, you’re going to have a bad day, over and over again.

Shockwaves from the explosion would spawn volcanoes and earthquakes around the globe, acid would rain down from the skies, wildfires would scorch the forests, and the world would be plunged again into an ice age by dust blocking out the sun.

• See a video of the Tsar Bomb exploding and try nuking your own home in our weird science blog at www.sundaymercury.net